> 1st one: point 4 (Unicode subdivision codes listed in emoji Unicode site)
> arises something like chicken-egg problem. Vendors don't easily add new
> subdivision-flags (because they aren't recommended), and Unicode doesn't
> recommend new subdivision flags (because they aren't supported by vendors).
>
​
That isn't really the case. In particular, vendors can propose adding
additional subdivisions to the recommended list. The UTC Consideration​s
<http://unicode.org/draft/emoji/selection.html#utc_consideration> would
come into play in assessing those proposals.​ So it is certainly possible
for there to be (say) a flag of Texas or Catalonia appearing in an Emoji
6.0 release this year. Similarly, Microsoft could propose adding the ninja
cat ZWJ sequences.